scholarly journals A Model for SynbioticActivity Evaluation: Static and Continuous Co-Culture Fermentation of BifidobacteriumAdolescentis ATCC 15703 and Bacillus Cereus ATCC 9634

2022 ◽  
Author(s):  
Svetlana Aleksandrovna Evdokimova ◽  
Vera Stanislavovna Nokhaeva ◽  
Boris Alekseevich Karetkin ◽  
Irina Vasilievna Shakir ◽  
Viktor Ivanovich Panfilov
Keyword(s):  
Gastrointestinal Tract ◽  
Flow Rate ◽  
Continuous Fermentation ◽  
Dynamic Balance ◽  
Lag Phase ◽  
Common Food ◽  
Keywords Probiotics ◽  
Medium Flow ◽  
Human Large Intestine ◽  
The Common

In this study, the ability of a probioticstrain (BifidobacteriumadolescentisATCC 15703) to inhibit the growth of the common food contaminantBacilluscereusATCC 9634was studied, both individually and as part of a synbiotic with FOS during batch or continuous fermentation (flow fermentation). The conditions of the flow fermentation corresponded to the parameters of the human large intestine: maintaining a pH of 6.8; anaerobiosis; and a medium flow rate of 0.04 h−1. Bifidobacteria and bacilli were co-cultivated on a prebiotic carbohydrate substrate (10 g/L) and the prebiotic was replaced with glucose (10 g/L).The results of the batch and flow fermentation were compared.The synbiotic efficacy of the probioticBif. adolescentisand the prebiotic FOSagainst the common food contaminantBac. cereuswas shown for all conditions. Fermentation of a pure culture of bifidobacteria with varying prebiotic concentrations (2, 5, 10, 15 and 20 g/L) was carried out to study the state of dynamic balance. It was demonstrated that 48 hours is enough to achieve stable dynamic balance.Prebiotics were co-cultivated with varying carbohydrate concentrations of 5, 10, and 15 g/L.The results showed that increasing the prebiotic concentration increased the duration of the lag-phase and reduced the final number of bacilli. Keywords: probiotics, prebiotics, synbiotics, gastrointestinal tract modeling, antagonism, co-culture fermentation

On an enclosed-design of chain drives for sucker-rod pumping units used in low and medium flow-rate wells

2018 ◽  
pp. 11-17
Author(s):  
V.M. Valovsky ◽  
◽  
K.V. Valovsky ◽  
I.G. Shamsutdinov ◽  
N.V. Fedoseenko ◽  
...  
Keyword(s):  
Flow Rate ◽  
Sucker Rod ◽  
Medium Flow ◽  
Pumping Units ◽  
Chain Drives

Radon removal by aeration: observations on testing, installation and maintenance of domestic treatment units

2009 ◽  
Vol 9 (4) ◽  
pp. 469-475
Author(s):  
T. Turtiainen
Keyword(s):  
Water Quality ◽  
Water Flow ◽  
Removal Efficiency ◽  
Flow Rate ◽  
Test Protocol ◽  
Household Water ◽  
Medium Flow ◽  
Removal Efficiencies ◽  
Frequent Sampling

Radon is one of the contaminants that sometimes impair the water quality of wells, especially those drilled in bedrock. Domestic radon removal units based on aeration have been commercially available for more than ten years. In order to determine how effectively these units remove radon a new test protocol applying frequent sampling while letting 100 litres of water flow, was developed. This way, removal efficiencies can be more accurately calculated and possible malfunctions detected. Seven models of domestic aerators designed for removing radon from household water were tested. The aerators were based on diffused bubble aeration, spray aeration or jet aeration. The average removal efficiencies for 100 litres with a medium flow rate were 86–100% except for a unit that circulated the aerated water back to the well that had removal efficiency of 80% at the maximum. By conducting a questionnaire study usual problems related to the aeration units were localized and recommendations on maintenance and installation are given accordingly.

Effects of stimulation on steroid output and perfusion medium flow rate in the isolated perfused rat adrenal gland in situ

1986 ◽  
Vol 109 (2) ◽  
pp. 279-285 ◽  
Author(s):  
J. P. Hinson ◽  
G. P. Vinson ◽  
B. J. Whitehouse ◽  
G. M. Price
Keyword(s):  
Flow Rate ◽  
Zona Glomerulosa ◽  
Clear Correlation ◽  
Perfusion Medium ◽  
Flow Rates ◽  
Vascular Elements ◽  
Medium Flow ◽  
High Concentrations ◽  
Adrenal Vasculature

ABSTRACT Using the in-situ, isolated, perfused rat adrenal system, the actions of adrenal stimulants on steroidogenesis and perfusion medium flow rates (under constant perfusion pump conditions) have been studied. In a series of 100 experiments, initial rates of corticosterone output and flow rates were found to be positively correlated, although there was no such relationship between initial rates of aldosterone output and flow rates. Furthermore, in stable perfusion conditions, bolus injections of ACTH increased both flow rate and steroid output in a dose-related manner. In individual experiments there was a clear correlation between corticosterone and flow, but the association between aldosterone secretion rate and flow was less evident. It is possible that this discrepancy arises because of temporal differences in the responses of these two steroids. Flow was also stimulated by dibutyryl cyclic AMP (dbcAMP), with correlations with steroid output similar to ACTH, but the specific zona glomerulosa stimulants angiotensin II amide and potassium ions had, if anything, inhibitory effects on flow, but only at high concentrations. The data suggest that ACTH and dbcAMP evoke specific responses in the adrenal vasculature, resulting in relatively decreased intraglandular vascular resistance. They furthermore suggest that the secretory functions of the inner adrenocortical zones are subject to the additional control of vascular elements in the intact gland. J. Endocr. (1986) 109, 279–285

Variability of Peak Hour Factor at Intersections

2005 ◽  
Vol 1920 (1) ◽  
pp. 125-130 ◽  
Author(s):  
Andrew P. Tarko ◽  
Rafael I. Perez-Cartagena
Keyword(s):  
Flow Rate ◽  
Field Measurements ◽  
Past Research ◽  
Time Of Day ◽  
Strong Impact ◽  
Field Observations ◽  
Average Value ◽  
The Common ◽  
Multiple Field ◽  
Over Time

A peak hour factor (PHF) is used to convert hourly traffic volume into the flow rate that represents the busiest 15 min of the rush hour. Past research indicated that PHF had a strong impact on traffic analysis results. The common practice is to use a default value recommended by national or local guidelines or to use limited field observations. This paper investigates the variability of PHF over time and across locations. The day-to-day variability of PHF was found to be as strong as the site-to-site variability. This finding prompts estimation of the PHF on the basis of multiple field measurements or, when it is not possible to obtain measurements, for the use of a model that returns the average value of PHF. This paper presents such a model, which links PHF with the hourly volume, population, and time of day. The paper demonstrates that a large portion of the variability in the sample of observations either can be explained with the model or can be attributed to the day-to-day fluctuation.

scholarly journals Siltation and Desilting Practices in A Runoff Reservoir on Heavy Sediment-Laden River

2018 ◽  
Vol 246 ◽  
pp. 01062
Author(s):  
Dangwei Wang ◽  
Anjun Deng ◽  
Zuwen Ji ◽  
Hongling Shi
Keyword(s):  
Flow Rate ◽  
Sediment Concentration ◽  
Reservoir Capacity ◽  
Power Station ◽  
Flood Season ◽  
Medium Flow ◽  
Key Factor ◽  
Diversion Channel ◽  
Dam Site ◽  
Sediment Deposit

Sediment deposition in the reservoir of run-of-the-river power station is severe, in this paper we take upper Marsyangdi reservoir as an example to analyze sedimentation and desilting process according field data measured from September 2016 when the reservoir had just been impounded in order to find strategy for managing reservoir sedimentation. The ratio of Upper Marsyangdi reservoir capacity and volume of sediment into the reservoir is about 0.2. The reservoir arrived silt-stable in a year after impoundment with a depth of 12m deposition at the dam site. Most of sediment deposit in the periods that at the initial and the end of flood reason and it is found the flow rate is the key factor influencing trap efficiency because that due to damming velocity of medium flow decreased significantly compared to natural condition which caused numerous deposition. Based on result of analysis of deposition the desilting condition is determined. Empty flushing is proposed to release deposition after flood season when flow rate is greater than 100m3/s and the new capacity will last to next flood season. In order to reduce sediment concentration into diversion channel a desilting should be done in flood season when flow rate is larger than 200m3/s and flow rate for impound should not be more than 1/10 of that into reservoir which can avoid deposition during impoundment near dam site.

scholarly journals Travel Time Model of Left-Turning Vehicles at Signalized Intersection

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Leng Jun-qiang ◽  
Feng Yu-qin ◽  
Zhai Jing ◽  
Bao Lei ◽  
He Yi
Keyword(s):  
Travel Time ◽  
Flow Rate ◽  
Signalized Intersection ◽  
Time Model ◽  
Through Flow ◽  
Negative Exponential Distribution ◽  
The Common ◽  
Queue Theory ◽  
Negative Exponential ◽  
The Impact

The travel time of left-turning vehicles at signalized intersection was discussed. Under the assumption that the opposing through vehicles headway follows M3 distribution, the travel time model was established on the basis of gap theory and queue theory. Comparison was done with the common model based on the assumption that the opposing through vehicles headway follows negative exponential distribution. The results show that the model in this paper has stronger applicability and its most relative error is less than 15%. In addition, the sensitivity analysis was done. The results show that the opposing through flow rate has significant impact on travel time. The impact of left-turning flow rate and following headway is light when the opposing through flow rate is small, the threshold is about 0.18 veh/s. The model established in this paper can well calculate travel time of left-turning vehicles at intersection, and the methodology may provide reference to other occasions.

scholarly journals Travel Time Model for Right-Turning Vehicles of Secondary Street at Unsignalized Intersections

2013 ◽  
Vol 2013 ◽  
pp. 1-6
Author(s):  
Feng Yu-Qin ◽  
Leng Jun-Qiang ◽  
Wang Peng ◽  
He Yi ◽  
Zhang Gui-e
Keyword(s):  
Travel Time ◽  
Poisson Distribution ◽  
Flow Rate ◽  
Erlang Distribution ◽  
Time Model ◽  
Unsignalized Intersections ◽  
Theory Comparison ◽  
The Common ◽  
Queue Theory ◽  
The Right

The travel time of right-turning vehicles on secondary street at unsignalized intersection is discussed in this paper. Under the assumption that the major-street through vehicles’ headway follows Erlang distribution and secondary-street right-turning vehicles’ headway follows Poisson distribution. The right-turning vehicles travel time model is established on the basis of gap theory and M/G/1 queue theory. Comparison is done with the common model based on the assumption that the major-street vehicles’ headway follows Poisson distribution. An intersection is selected to verify each model. The results show that the model established in this paper has stronger applicability, and its most relative error is less than 15%. In addition, the sensitivity analysis has been done. The results show that right-turning flow rate and major-street flow rate have a significant impact on the travel time. Hence, the methodology for travel time of right-turning vehicles at unsignalized intersection proposed in this paper is effective and applicable.

Separation of hepatic and gastrointestinal signals from the common “hepatic” branch of the vagus

2004 ◽  
Vol 287 (1) ◽  
pp. R120-R126 ◽  
Author(s):  
Charles C. Horn ◽  
Mark I. Friedman
Keyword(s):  
Gastrointestinal Tract ◽  
Jugular Vein ◽  
Nerve Activity ◽  
Hepatic Hilus ◽  
Afferent Fibers ◽  
Neurophysiological Studies ◽  
Before And After ◽  
The Common ◽  
Hepatic Branch

Anatomic studies show that the common hepatic branch (CHB) of the vagus contains afferent fibers that innervate sites outside the hepatoportal region, primarily in the gastrointestinal tract. In the current experiments on the anesthetized rat, the source of signals from the CHB was determined by recording CHB neurophysiological responses before and after transection of the gastroduodenal branch (GDB) of the CHB. Serotonin [5-hydroxytryptamine (5-HT)] and CCK-8 were used as probes to stimulate the CHB. Most of the CHB afferent fibers were 5-HT sensitive (56%), and 35% of these were also sensitive to CCK-8. Portal vein vs. jugular vein infusion of 5-HT and CCK-8 and GDB transection showed that 5-HT- and CCK-sensitive fibers innervate the hepatoportal region and areas outside the hepatic hilus (e.g., the gastrointestinal tract). Suppression of basal nerve activity by a 5-HT3 receptor antagonist (Y-25130) suggests that ∼50% of CHB afferent fibers contain 5-HT3 receptors, but none of these fibers appears to be in the hepatoportal region because only in rats with an intact GDB did Y-25130 reduce nerve activity. In summary, these data are in close agreement with anatomic observations on the distribution of the CHB fibers and indicate that neurophysiological studies of the CHB must be carefully evaluated given the prominent role of nonhepatoportal afferent signals recorded from the CHB.

scholarly journals On feeding of deep-sea crabs on the continental slope of northwestern Kamchatka

2016 ◽  
Vol 184 (1) ◽  
pp. 236-240
Author(s):  
Valery I. Chuchukalo ◽  
Victor A. Nadtochy ◽  
Vladimir V. Napazakov ◽  
Oleg Yu. Borilko ◽  
Sergei A. Nuzhdenko
Keyword(s):  
Gastrointestinal Tract ◽  
Continental Slope ◽  
Deep Sea ◽  
Frequent Occurrence ◽  
King Crab ◽  
Common Food ◽  
Tanner Crab ◽  
The Mean ◽  
Main Components

Mean index of gastrointestinal tract fullness for golden king crab Lithodes aequispinus is 15.5 ‱. Detritus occurs in 40.5 % of the cases, so it is a common food for this crab, Polychaeta, Ophiuroidea and Decapoda are 33.2 %, 32.1 % and 15.4 % of its ration, respectively, whereas Mollusca are only 11.5 % of the ration weight, despite of frequent occurrence. Triangle tanner crab Chionoecetes angulatus has the mean index of fullness 20.9 ‱, Polychaeta and Mollusca are two main components of its ration (31.4 % and 27.3 %, respectively) and Decapoda and Pisces are the secondary components (13.9 % and 12.2 %); detritus occurs in 11.2 % of the cases. Cannibalism is observed incidentally for the latter species.

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